Flexible ledger-leaf.



R. KHUMMING.

FLEXIBLE LEDGER LEAF.

APPLICATION FILED JAN. 5, I914.

1,199,280. Patented Sept. 2 1916.

mww #MW M Gum/M24 8 REINHOLD KRUMMING, 0F MILWAUKEE, WISCONSIN.

FLEXIBLE LEDGER-LEAF.

maeso.

Specification of Letters Patent.

Patented Sept. 26, 1916.

Application filed. January 5, 1914. Serial No. 810,359.

To all whom it may concern:

Be it known that I, ItnrNrIoLD KRUM- MING, a citizen of the United States, residing at Milwaukee, \Visconsin, have invented certain new and useful Improvements in a Flexible Ledger-Leaf, of which the following is a specification.

This invention relates to improvements in a flexible ledger leaf.

Sheets or leaves used for ledger or record purposes are commonly of quite heavy stiflf paper. Sheets or leaves of that character, particularly when used in certain wellknown types of temporary binders or loose sheet holders, owing to the manner in which they are bound, or retained in the binders, do not lie flat unless some provision is made for hinging or flexing portions for the sheets.

It is the main object of this invention to provide an improved sheet or leaf which is very flexible at the Zone of flexure and at the same time one which is not likely to tear or break at that point, and further, one which is very economical to produce.

Further objects, and objects relating to structural details, will definitely appear from the detailed description to follow.

I accomplish the objects of my invention by the devices and means described in the following specification.

The invention is clearly defined and pointed out in the claims.

A structure which is a preferred embodiment of my invention is clearly illustrated in the accompanying drawing forming a part of this specification, in which:

Figure I is a plan view of one of my improved sheets .or leaves, the outer end of the sheet being broken away. F ig.,II is an enlarged detail section on a line corresponding to the line 22 of Fig. I.

In the drawing similar reference numerals refer to similar parts in both views.

Referring to the drawing, the sheet 1 is shown ruled as an ordinary ledger sheet. At its rear edge the sheet is provided with suitable keyhole slots 2 which may be engaged with the posts of a temporary binder such, for instance, as is shown in my patent No. 1,017 ,220, of Feb. 13, 1912, my improved sheet being especially designed by me and well adapted for use in post binders. It is, however, desirable for use in other types of binders and is of advantage in cer tain permanently bound books.

At the zone of fleXure I form a series of parallel scores 3 on both sides, with the scores on opposite sides alternating. This produces a corrugated or crimped eifect as shown in Fig. II. The scores are arranged in groups, there being unscored portions 1 between the groups and between the groups and the edges of the sheet. These scores are preferably not distinct cuts but are preferably formed by crimping rollers or dies which break and loosen the fibers to a degree which renders the sheets very flexible at this zone of flexure- By alternating the scores on opposite sides of thesheets, the sheet is equally flexible in both directions, and the strain of bending or flexing is equalized or distributed throughout the area of the scored or crimped hinge portion.

By providing an unscored or uncrimped portion between the groups of scores and between the scores and the edges of the sheets, the sheet is prevented from tearing or breaking from turning or handling.

My improved sheet or leaf is very flexible at the zone of flexure and is very economical to produce, and, as stated, is not likely to be torn in use.

In practice, I preferably form the flexible portion during the process of printing. The mechanism by which I preferably accomplish this is shown in my application for patent on printing machine attachment filed concurrently herewith.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A sheet or leaf having at the Zone of flexure a series of parallel scores on both sides with the scores on opposite sides alternating, the scores being arranged in groups with unscored'portions between the groups and between the groups and the edges of the sheet, the unscored portions on opposite sides of the sheet being opposite and continuous from the binding edge to the body of the sheet. I

2. A sheet or leaf having groups of In Witness whereof, I have hereunto set orimps at the point of fiexure with un-' my hand and seal in the presence of tWo witcrimped portions between the groups and nesses. between the groups and the edges of the REINHOLD KRUMMING. [L.s.]

5 sheet, the uncrimped portions being rela- WVitnesses:

tively narrow and continuous from the hind.- W'. T. V000, ing edge to-the body of the sheet. A. P" BRATZ.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patent Washington, IL 0. 

